As technology advances, the options for communications have become more varied. For example, in the last 30 years in the telecommunications industry, personal communications have evolved from a home having a single rotary dial telephone, to a home having multiple telephone, cable and/or fiber optic lines that accommodate both voice and data. Additionally cellular phones and wireless networks have added a mobile element to communications.
The possibility of identifying the geographical location of users in cellular networks has enabled a large variety of commercial and non-commercial services, e.g., navigation assistance, social networking, location-aware advertising, emergency calls, etc. Different services may have different positioning accuracy requirements imposed by the application. In addition, some regulatory requirements on the positioning accuracy for basic emergency services exist in some countries, i.e. Federal communications Commission (FCC) Emergency 911 (E911) in US.
The accuracy of the provided result, as well as the response time, depend on a number of factors such as propagation environment, terminal capability, network capability, requested quality of service (QoS), positioning methods availability, and positioning method selection procedure. At least the following positioning technologies are currently being considered for Long Term Evolution (LTE): Assisted Global Navigation Satellite System (A-GNSS), Time Difference of Arrival (TDOA), Fingerprinting, Cell ID (CID), Enhanced CID (E-CID), Adaptive Enhanced CID (AECID), Angle of Arrival (AoA) and Hybrid positioning. Uplink Time Difference of Arrival (U-TDOA) is still under discussion in the 3rd Generation Partnership Project (3GPP). The variety of the standardized methods is explained not only by the range of applications and location services (LCS), but also by their environment- and deployment-dependent performance. In the challenging environments, different methods may also complement each other to achieve the desired accuracy, e.g. by being hybridized. It has also been shown that using various types of measurements and positioning-related information can enhance positioning performance significantly, which is exploited, for example, in the AECID method.
In any positioning architecture, the following three network elements are important: the LCS client, the LCS target and the LCS server. The LCS server is a physical or logical entity managing positioning for a LCS target device (such as User Equipment (UE), user terminals and radio nodes in general, e.g. sensor, relay, small base stations) by obtaining measurements and other location information, providing assistance data to assist the LCS target device in measurements, and computing, or verifying the final position estimate. Examples of LCS servers in LTE are Evolved Serving Mobile Location Center (E-SMLC) in a the control plane solution and Secure User Plane Location (SUPL) Location Platform (SLP) in a user-plane solution, both referred to as a positioning node herein.
The positioning function may reside in a terminal (e.g. with UE-based positioning), radio network node (e.g. Radio Network Controller (RNC) in a Universal Mobile Telecommunications System (UMTS)) or a core network node (e.g. positioning node in UE-assisted or network-based positioning). The input to the positioning function, which performs the actual positioning of a specific target node (e.g., a terminal or radio node), is a positioning request from an LCS Client with a set of parameters such as QoS requirements. The end results of the positioning function are the location information for the positioned target node communicated as a part of the positioning response. An LCS client is a software and/or hardware entity which may or may not reside in the target node being positioned. The LCS client may be internal or external to the Public Land Mobile Network (PLMN). The positioning result is communicated at least to the requesting entity but possibly also to other nodes, including the terminal itself.
The location information may be requested by and reported to an LCS Client associated with a UE or radio node, or by an LCS Client within or attached to the Core Network. The location information may also be utilized internally in the system; for example, for location-assisted handover or to support other features such as home location billing. The location information request may also ask for the velocity of the as part of the positioning information.
The positioning target may be any device that is being positioned. This can be a UE, a laptop, or a terminal in a more general sense or it may even be a small radio node such as abuse station, access point, relay, repeater, beacon device, etc. The terms ‘terminal’ or ‘UE’ are used herein interchangeably with ‘positioning target’, but the non-limiting terminology can be easily understood by the skilled in the art.
Due to the above, the target nodes may have different characteristics and thus may have different capabilities which may impact the amount and the contents of any downloaded assistance information, the set of feasible reporting formats, and the positioning method selection. The target node capability my be signaled to the network together with the positioning request or may be requested later by the positioning server prior to calling the positioning function. To inform the target node on network capabilities, e.g., the set of available positioning methods, the network capability information may also be communicated to the target node.
In many of the devices storing positioning information, part of the positioning information may be provided by the end user and may be entered in a language other than the default language of the local area. For example, positioning information entered in Spanish in an English language country. Accordingly, locating a particular device on a cellular network can be enhanced by employing positioning information to identify the location of the device. As indicated above the use of this information requires the ability to translate the positioning information between different languages.
Consequently, market pressure is building for a solution which would allow an end user to enter positioning information in a language of their choice and allow the positioning information to be usable, in a translated format, by other nodes on the network for locating the device. Accordingly, the ability to translate positioning information from a language entered at a node or device to a language required or preferred by other node or device. For example, it may be ensured that the positioning information received from the positioning node by the target device or Emergency-911 Public Safety Answering Point (PSAP) can be understood and the dispatch of emergency services to a location occurs with a greater degree of accuracy.